SEATTLE (AP) _ It's not usually a good idea to upset Cal Ripken. Unless he takes it out on someone else.

Ripken, assured he will not be forced to play third base, hit three homers in a game for the first time and drove in a career-high eight runs in leading the Baltimore Orioles over the Seattle Mariners 12-8 on Tuesday night.

``If I have to hack him off every night to get him to hit three home runs I'll do it,'' Baltimore manager Davey Johnson said. ``Maybe I'll ask him to DH tomorrow.''

Ripken hit a grand slam and a pair of two-run homers. He began the day with only three homers this season, but wound up tying Eddie Murray for the team's career home run lead with 333.

``It'd be a nice story to say that finally having that weight off my shoulders about moving to third helped me accomplish what I did tonight,'' Ripken said. ``I'm not sure it's true.''

Johnson said last week that Ripken, a 13-time All-Star shortstop, was likely to be moved to third base either during the Memorial Day weekend or during the series in Seattle because of injuries.

Ripken and Johnson, however, talked before Tuesday's game, and the manager said that notion is now ``on the backburner.''

Ripken has started Baltimore's last 2,174 games at shortstop, dating back to 1982. He has played 2,221 in a row overall, having started the streak as a third baseman.

After Ripken hit a two-run homer in the ninth, his brother Bill _ who started at third base _ also homered. It was the second time the Ripkens have homered in the same game, and the 16th time in major league history that brothers have connected in the same game.

``Any time you see your bro hit one deep and then you get one yourself, it's a pretty special feeling,'' Bill Ripken said.

``It's nice for Bill to get a chance to play again and to get a chance to hit a homer again,'' Cal Ripken said.

Brady Anderson hit his seventh leadoff homer of the season _ and No. 19 overall _ and Rafael Palmeiro hit a two-run shot for the Orioles, who scored all of their runs on homers.

Ken Griffey Jr. hit his 16th home run for Seattle.

Cal Ripken's two-run homer of Bob Wolcott put Baltimore ahead 3-1 in the fourth inning. His fifth career grand slam, off Mike Jackson, gave the Orioles a 9-6 lead in the seventh. Ripken homered off Scott Davison in the ninth.

``I made a bad pitch and he hit it out,'' Jackson said. ``He's hitting the ball very well right now.''

Arthur Rhodes (5-0) pitched 1 2-3 innings for the win, striking out three. Jimmy Haynes got his first save.

Lee Guetterman (0-1) loaded the bases with a single and two walks in the seventh. He was replaced by Jackson, who gave up Ripken's grand slam on the first pitch.

Alex Rodriguez, Edgar Martinez and Jay Buhner all hit RBI doubles in the fifth inning as the Mariners rallied from a four-run deficit to take a 6-5 lead.

Baltimore's Scott Erickson made his first start since spraining an ankle during pre-game drills on May 13 in Oakland, but gave up eight hits and six earned runs in 4 2-3 innings.

Notes: The Ripkens were the last brothers to homer in the same game, doing it on Sept. 15, 1990. ... Billy Ripken hit his first home run of the season. ... Cal Ripken has 15 multi-homer games. ... Roberto Alomar of the Orioles has a 13-game hitting streak. ... Rodriguez and Martinez have 11-game hitting streaks. ... The Mariners transferred Chris Bosio, who has inflammation and arthritis in his right knee, from the 15- to the 60-day disabled list.